The reference to fueling provides a potential marriage between SLS and propellent depots, something which would partially appease some critics, given the remaining anti-SLS activists are now focusing on the use of the popular prop depot architecture as a full alternative to the HLV.Ironically, some Prop Depot designers along with several NASA HLV presentations over recent years have advocated the use of both strengths in tandem. This was also a major element of what remains the most expansive HLV overview in recent times
Chris;I may be mis-reading the article but I got the feeling that the "in-line" design was NOT a 'sure-thing' at this point and there might still be a version of the side-mount in consideration. Did I get that wrong or is the design actually "finalized" as far as the basic configuration goes?Randy
Great Article Chris! Lunar First is really intriguing as part of a larger, flexible BEO path. Does Lunar First require additional funding or can it fit within current budgets?
Quote from: Khadgars on 10/25/2011 10:32 pmGreat Article Chris! Lunar First is really intriguing as part of a larger, flexible BEO path. Does Lunar First require additional funding or can it fit within current budgets?Thanks! I really do not know. I've always "avoided" dollar amounts, partly because the documentation we gain doesn't contain numbers (if it did, it might be heavily restricted too - so it's always interesting when some sites say there's no money, meaning they either have content they shouldn't or are assuming it), but they have a projection of funding and they can mix and match the best roadmap from that - as is being done right now.You did see a potential future get-well added to the article, which sounded a bit op-ed, but was actually mentioned to me, which was to forget about the 130mt. SLS Block 1 and 1A brings a lot of capability to the table, and one needs to consider if having that extra 25mt is really worth what it'd cost to have 130mt with all its whistles and bells - especially IF it's stretching the schedule for the flagship BEO missions.
Postponing the 130 tonne vehicle for a decade or 2 is, in my opinion, a really good idea. And if they do that then they:(1) don't have to stretch the tank, (2) don't need the 5th center SSME and (3) can leave out the center segment of the 5-segment booster and fly it with just 4 segments and 3 SSME's. Leave the TS configured for 4 SSME's but when flying without the upper stage and only 3 SSME's it will easily lift 70 tonnes to LEO - (*plus* ) - and will easily go to 100 tons by adding an upper stage and the 4th SSME or the center segment and an SSME. Keep the stretched tank, bigger SRB and extra SSME for when we really need to lift 130 tonnes from the ground, which, if the depots are brought on line, could be decades. This would save a *lot* of money that could be redirected to payload development, or maybe even a (gasp) "lander".
So you want the SLS to be a J-130. Reasonable, but everything I've seen shows that all configurations will be stretched.
The NASA's poster related to the article can be found at: http://www.nasa.gov/pdf/594163main_2011-SLS_Industry_Day_Final_Public1-1_rev2.pdf
[Concur.Propellant depots can really be a game changer for some missions, and I personally don't beleive they need all that extra performance from the vehicle, only its fairing size.
Presentation said that 130 mT vehicle would fly with 3 RS-25s. Is that right? I thought the final evolved vehicle would use 5.
Good to see that NASA is using the correct abbreviation for 1000 kg = 1 tonne (t). An mt (millitonne = 1 kg), Mt (megatonne = 1,000,000,000 kg), mT (milli Tesla = 0.001 T) and MT (mega Tesla = 1,000,000 T) are all incorrect! :-)
Quote from: clongton on 10/25/2011 11:53 pmPostponing the 130 tonne vehicle for a decade or 2 is, in my opinion, a really good idea. And if they do that then they:(1) don't have to stretch the tank, (2) don't need the 5th center SSME and (3) can leave out the center segment of the 5-segment booster and fly it with just 4 segments and 3 SSME's. Leave the TS configured for 4 SSME's but when flying without the upper stage and only 3 SSME's it will easily lift 70 tonnes to LEO - (*plus* ) - and will easily go to 100 tons by adding an upper stage and the 4th SSME or the center segment and an SSME. Keep the stretched tank, bigger SRB and extra SSME for when we really need to lift 130 tonnes from the ground, which, if the depots are brought on line, could be decades. This would save a *lot* of money that could be redirected to payload development, or maybe even a (gasp) "lander".Concur.Propellant depots can really be a game changer for some missions, and I personally don't beleive they need all that extra performance from the vehicle, only its fairing size.
Exciting stuff. Can't wait to see the R-25s fly again. Won't they need a habitation module of some kind to do the deep space? Seems unreasonable to make a long voyage in the Orion itself.
Won't they need a habitation module of some kind to do the deep space? Seems unreasonable to make a long voyage in the Orion itself.
Cannot wait to see the moon is HD 3D! NASA should set the goals...Lunar Manned fly-by 2018!Lunar Landing 2019!
You did see a potential future get-well added to the article, which sounded a bit op-ed, but was actually mentioned to me, which was to forget about the 130mt. SLS Block 1 and 1A brings a lot of capability to the table, and one needs to consider if having that extra 25mt is really worth what it'd cost to have 130mt with all its whistles and bells - especially IF it's stretching the schedule for the flagship BEO missions.
Awesome, I wasn't aware they could stretch Black 1 into 105mt. That seems to make so much more sense and would save a lot of money. I'm curious how that conflicts with what Congress has mandated?
MPLM Leonardo, for example?
I noticed in the article under the heading SLS at KSC that the engineers are planning to design a new flame deflector for Pad 39B. This tidbit almost got lost in the discussion but it is pretty significant. One of the objections to starting off using the SRB on SLS Block 1 and not waiting for the Booster Compete is that the LRB people feel that the pad mods needed to accommodate *any* LRB design would be precluded, most notably the flame deflector. It was designed for the SRBs and could not accommodate the larger diameter LRBs. Some have claimed that unless the flame deflector change is done now that there would be no budget for it later, and the LRBs would be effectively shut out. Well it seems that the engineers are having none of that outmoded thinking and LRBs are being considered in the pad modifications. The flame deflector is being redesigned and with a little imagination the entire flame trench/deflector system should be able to accommodate the larger LRBs as well as the SRBs.Im impressed. There is a lot of forward thinking, followed by action, going on.
Quote from: Khadgars on 10/26/2011 02:18 amAwesome, I wasn't aware they could stretch Black 1 into 105mt. That seems to make so much more sense and would save a lot of money. I'm curious how that conflicts with what Congress has mandated?I think the Block 1A has the same core as the Block 1, just the boosters are upgraded. Either new SRB's with light composite casings and new propellent mixture, or LRB's. That gives it the boost in capacity. The core will be the same though, not "stretched". Block 1 core will be a "stretched" ET. The stretch is from the get go.
I wonder if there is any chance of moving the first flight test from 2017 to 2016?
I think they can go ahead and start flying mission with the Block I and maybe fund a DTAL style lander and fuel depot and put the IA SLS as a later upgrade vs having a four year gap between flights.As for the SRB upgrades are they even needed?
The light weight composite SRB definitely would be a complete waste of money and the LRB only makes sense if there is an F-1A class engine that's relatively cheap or if the LRB is reusable.
The five segment RSRM should be able to handle any payload that comes along for the next 15 to 20 years so long as they design the architecture around the LVs.
One thing the designers seems to be overlooking is the law of diminishing returns getting an extra 20 mT out of a 130 mT LV simply is not worth 8B of R&D.It would be better to fly what you have more often and get lower cost.
Nitpick: SI units (though not the symbols for them) are in lower case by default, even when derived from people's names. Thus the SI unit of magnetic induction is the tesla, and million of them make a megatesla.
Thanks! I don't think this would be a JWST. It'd be something bigger - which is a problem as it'd cost a lot.
Thanks Bill! I know people may get sick of me saying that on the thread, but it does mean a lot. I'd be a bit pointless if I wasn't writing content that was enjoyed by the readership.I know I've left this one top for a day longer than planned (wrote a big article yesterday, but held via an embargo), but this one is about to go through 100,000 reads (97,109 right now), so there's a lot of interest too, which is good!
Postponing the 130 tonne vehicle for a decade or 2 is, in my opinion, a really good idea.<snip>
Great article Chris. ...
Just read this and that's one very comprehensive article!You'd save time, however, writing a 200 word op-ed about how SLS sucks and then get gleefully linked by the nuspace gang.
Quote from: Maverick on 10/29/2011 12:04 pmJust read this and that's one very comprehensive article!You'd save time, however, writing a 200 word op-ed about how SLS sucks and then get gleefully linked by the nuspace gang.Except that the SLS doesn't suck. It may not be the best technical choice but it works and works pretty well.
SLS may not look like the best alternative to some (myself included) but from the perspective of the option that has funding, it is the best alternative until such time as something better with equal or more capability is public or privately funded.
In the end, it is the SLS configuration we currently have that has gotten the nod - and more importantly - the funding. No matter what we all think, it is this SLS that got the nod and it is this SLS that will take us back to the Moon.
It got funding this year. It remains to be seen whether it will get the funding necessary to sustain it next year, and the year after that, and so forth, for as long as required to get back to the moon. -Alex
Quote from: clongton on 10/29/2011 06:22 pm In the end, it is the SLS configuration we currently have that has gotten the nod - and more importantly - the funding. No matter what we all think, it is this SLS that got the nod and it is this SLS that will take us back to the Moon. It got funding this year. It remains to be seen whether it will get the funding necessary to sustain it next year, and the year after that, and so forth, for as long as required to get back to the moon. -Alex
Quote from: alexw on 10/29/2011 08:29 pmQuote from: clongton on 10/29/2011 06:22 pm In the end, it is the SLS configuration we currently have that has gotten the nod - and more importantly - the funding. No matter what we all think, it is this SLS that got the nod and it is this SLS that will take us back to the Moon. It got funding this year. It remains to be seen whether it will get the funding necessary to sustain it next year, and the year after that, and so forth, for as long as required to get back to the moon. -AlexAh. Glass half empty kind of guy.
IMHO, the key to that is visible fast progress. The faster and more visible, the less able Congress will feel to cancel, either overtly or covertly by defunding.For all it has the feel of Ares-I-X, an SLS-X mission using the last surviving LWT, four-segs and SSMEs may be critical in that endeavour.
No, he's just being a realist. CxP was the program of record and supported by Congress for years. How did that end up? You just have to hope for the best, and expect be prepared to handle the worst. SLS being "the law" right now offers precious little guarantees for a few years down the line. Making progress and not wasting resources is NASA's best defense.
Quote from: Lars_J on 10/30/2011 01:51 amNo, he's just being a realist Pessimist. CxP was the program of record and supported by Congress for years. How did that end up? You just have to hope for the best, and expect be prepared to handle the worst. SLS being "the law" right now offers precious little guarantees for a few years down the line. Making progress and not wasting resources is NASA's best defense.Fixed that for ya
No, he's just being a realist Pessimist. CxP was the program of record and supported by Congress for years. How did that end up? You just have to hope for the best, and expect be prepared to handle the worst. SLS being "the law" right now offers precious little guarantees for a few years down the line. Making progress and not wasting resources is NASA's best defense.
SLS is NOT CxP; for one it doesn't have the problem of a STICK to worry about; this is a one shot vehicle (rocket) with an evolutionary path that doesn't require two individual rockets following their own paths, to build a LV architecture; my apologies if my wording is wrong, but anyone who has been around here 2-3 years will understand; {snip}
Quote from: cro-magnon gramps on 10/30/2011 08:00 amSLS is NOT CxP; for one it doesn't have the problem of a STICK to worry about; this is a one shot vehicle (rocket) with an evolutionary path that doesn't require two individual rockets following their own paths, to build a LV architecture; my apologies if my wording is wrong, but anyone who has been around here 2-3 years will understand; {snip}A Moon landing with the 70 tonne payload SLS is likely to need 2 launches. One SLS takes the lander to lunar orbit where it rendezvous with the manned Orion brought by the other SLS LV.Manned Mars missions are likely to need several of the larger SLS LV.
A Moon landing with the 70 tonne payload SLS is likely to need 2 launches. One SLS takes the lander to lunar orbit where it rendezvous with the manned Orion brought by the other SLS LV.
4 man reusable lander visiting multiple sites is what I'd like to see.Fuel depot in LLO or EML1 could be done.Getting large cargo to the moon should be done separate and later on after a suitable site for a base is found.Moonhabs will not be cheap. International co-op might be needed.
I think an Apollo style mission isn't going to get enough done.....Moonhabs will not be cheap. International co-op might be needed.
I am wondering, why cannot we move forward with a proposal such as this:1. Indefinitely delay development of the J-2X and the upper stage. 2. Begin immediate development of the CPS, using RL-10 engines. 3. Indefinitely delay, or cancel, any plan to change the boosters. Simply complete development of the 5 segment SRB. Lunar missions could then begin with dual launches. One launch to carry the CPS and a second launch carrying Orion and the LSAM. We could then move onto developing a fuel depot to refuel the CPS.
Quote from: Mr. Justice on 11/21/2011 03:24 amI am wondering, why cannot we move forward with a proposal such as this:1. Indefinitely delay development of the J-2X and the upper stage. 2. Begin immediate development of the CPS, using RL-10 engines. 3. Indefinitely delay, or cancel, any plan to change the boosters. Simply complete development of the 5 segment SRB. Lunar missions could then begin with dual launches. One launch to carry the CPS and a second launch carrying Orion and the LSAM. We could then move onto developing a fuel depot to refuel the CPS. I already have a poll request similar to what you said.What you said is a good idea. A future congress if it ever needed a bigger that 70t to LEO could then add the upper stage and/or advance LRB's or SRB's.
Quote from: Steven Pietrobon on 10/26/2011 06:14 amGood to see that NASA is using the correct abbreviation for 1000 kg = 1 tonne (t). An mt (millitonne = 1 kg), Mt (megatonne = 1,000,000,000 kg), mT (milli Tesla = 0.001 T) and MT (mega Tesla = 1,000,000 T) are all incorrect! :-)Thanks for pointing this out; it makes me happy.Nitpick: SI units (though not the symbols for them) are in lower case by default, even when derived from people's names. Thus the SI unit of magnetic induction is the tesla, and million of them make a megatesla.
Quote from: Mr. Justice on 11/21/2011 03:24 amI am wondering, why cannot we move forward with a proposal such as this:1. Indefinitely delay development of the J-2X and the upper stage. 2. Begin immediate development of the CPS, using RL-10 engines. 3. Indefinitely delay, or cancel, any plan to change the boosters. Simply complete development of the 5 segment SRB. Lunar missions could then begin with dual launches. One launch to carry the CPS and a second launch carrying Orion and the LSAM. We could then move onto developing a fuel depot to refuel the CPS. 1. Actually, that's kind of what the plan is.2. What you're hoping for, then, is to see the CPS proposed in the next President's Budget Request, in February. The CPS has been studied quite a bit, internally, so it could be proposed. However, it's not in the NASA Authorization Law, which goes through 2013. That's not necessarily a show-stopper, but I don't expect to see it show up in a budget request until the FY2014 request, which comes out in February 2013. That assumes, of course, money is found for the project.3. We can't get 105t to orbit without the advanced boosters.And the problem with lunar surface missions is the President's policy of going to an asteroid next.
Nitpicking contest?
2. I envision the CPS as being merely an enlarged Delta IV upper stage.
Quote from: Starlab90 on 11/21/2011 11:41 pmQuote from: Mr. Justice on 11/21/2011 03:24 amI am wondering, why cannot we move forward with a proposal such as this:1. Indefinitely delay development of the J-2X and the upper stage. 2. Begin immediate development of the CPS, using RL-10 engines. 3. Indefinitely delay, or cancel, any plan to change the boosters. Simply complete development of the 5 segment SRB. Lunar missions could then begin with dual launches. One launch to carry the CPS and a second launch carrying Orion and the LSAM. We could then move onto developing a fuel depot to refuel the CPS. 1. Actually, that's kind of what the plan is.2. What you're hoping for, then, is to see the CPS proposed in the next President's Budget Request, in February. The CPS has been studied quite a bit, internally, so it could be proposed. However, it's not in the NASA Authorization Law, which goes through 2013. That's not necessarily a show-stopper, but I don't expect to see it show up in a budget request until the FY2014 request, which comes out in February 2013. That assumes, of course, money is found for the project.3. We can't get 105t to orbit without the advanced boosters.And the problem with lunar surface missions is the President's policy of going to an asteroid next. 1. As I understand it, the initial CPS is just the Delta IV kick-stage. Then the CPS would be built sometime in the early 2020s. 2. I envision the CPS as being merely an enlarged Delta IV upper stage. While I am not expert on the subject, I believe this would cost very little money and very little time. Thus, it would seem possible the CPS could fly less than fully fueled on the 2017 SLS flight, as opposed to the Delta IV kick-stage. 3. Is there anything magical about 105 tons? Regardless, my point is if we spend the money to upgrade the boosters that is money we are not spending to begin exploration missions. I do not necessarily oppose upgrading the booster at some point in the future.4. Obama did not prevail with respect to not returning to the Moon. There are also indications, as previous mentioned by Chris, that NASA is discussing a Lunar Surface First approach. 42 U.S.C. § 18321(a)(1); http://www.nasaspaceflight.com/2011/10/space-bound-orion-lunar-missions-referenced/
3. What is "magical" about 105t is it is a requirement that has been imposed on the SLS Program by NASA HQ.
Quote from: Starlab90 on 11/29/2011 12:34 am3. What is "magical" about 105t is it is a requirement that has been imposed on the SLS Program by NASA HQ.What is the basis for this 105t requirement imposed by NASA HQ? It is not in the authorization act, so it should not be driving the SLS design in any way. It seems perfectly reasonable to postpone development of any advanced boosters until we actually need them.
Quote from: Mark S on 11/29/2011 11:18 pmQuote from: Starlab90 on 11/29/2011 12:34 am3. What is "magical" about 105t is it is a requirement that has been imposed on the SLS Program by NASA HQ.What is the basis for this 105t requirement imposed by NASA HQ? It is not in the authorization act, so it should not be driving the SLS design in any way. It seems perfectly reasonable to postpone development of any advanced boosters until we actually need them.The information's not yet publicly available, but a number of the DRMs developed by the HEFT and HAT teams only require 105t. This includes both lunar and NEA DRMs.
Quote from: Starlab90 on 11/30/2011 12:34 amQuote from: Mark S on 11/29/2011 11:18 pmQuote from: Starlab90 on 11/29/2011 12:34 am3. What is "magical" about 105t is it is a requirement that has been imposed on the SLS Program by NASA HQ.What is the basis for this 105t requirement imposed by NASA HQ? It is not in the authorization act, so it should not be driving the SLS design in any way. It seems perfectly reasonable to postpone development of any advanced boosters until we actually need them.The information's not yet publicly available, but a number of the DRMs developed by the HEFT and HAT teams only require 105t. This includes both lunar and NEA DRMs.That would seem to make sense. And it would also seem to be consistent with logic that Congress is not going to "force" 130 mT rocket on NASA if it does not require it right now, regardless of what the "Senate Launch System" arm-wavers want to try to promote. Hopefully Shannon and his DRMs (followed up immediately with real objectives for making them reality) are made known to all soon.
SLS isn't too big.After you add the EDS and Mars aeroshell how much are you left with for EDL?"Ultimate destination of Mars"The SLS is not a moon/asteroid rocket even if it can do those things in the interim.Administrator Bolden said it well "Everybody wants to go to Mars".Detour programs are a waste of time and money. I don't see any calls for a lunar lander to be funded? They want the deep space hab for long range spaceflight.
Quote from: spectre9 on 11/30/2011 02:01 amSLS isn't too big.After you add the EDS and Mars aeroshell how much are you left with for EDL?"Ultimate destination of Mars"The SLS is not a moon/asteroid rocket even if it can do those things in the interim.Administrator Bolden said it well "Everybody wants to go to Mars".Detour programs are a waste of time and money. I don't see any calls for a lunar lander to be funded? They want the deep space hab for long range spaceflight.So you make your BFR. You then have no money for an EDS and aeroshell, so there's no mission.DSH is not funded.
SLS isn't too big.
I was talking about capability and missions and now I'm being slapped with the cost argument?This has been done to death already.Senator Hutchison has told us SLS/MPCV will get full funding in 2012 and will not be short changed in 2013.Why are you being so cynical clongton?Why does SLS Block 2 in particular seem like a money muncher?
Quote from: spectre9 on 11/30/2011 10:22 amI was talking about capability and missions and now I'm being slapped with the cost argument?This has been done to death already.Senator Hutchison has told us SLS/MPCV will get full funding in 2012 and will not be short changed in 2013.Why are you being so cynical clongton?Why does SLS Block 2 in particular seem like a money muncher?Why so cynical? Well, I can't speak for clongton, but how about the fact the Congress has specified in detail the kind of rocket it wants built, which it has neither the responsibility nor the competence to do, but has yet to say much about what it wants NASA to do with that rocket? In fact, it's positively avoiding the question of what to do with the rocket. The 2010 NASA Authorization Act directs that the National Academy of Sciences study what to do with the rocket, but clearly specifies that the report is to be commissioned only in 2012, so it will not be released until after the 2012 election.If the Congress were serious about exploring space, it would, after reviewing the likely costs, direct NASA to do so and leave NASA's engineers to choose the appropriate hardware.
NASA and the senate went back and forth for a long time trying to figure out the best way to build a next generation lifter using legacy hardware.To say that senate designed the rocket isn't just false it a flat out lie that shouldn't be propagated at all.
Quote from: spectre9 on 11/30/2011 03:53 pmNASA and the senate went back and forth for a long time trying to figure out the best way to build a next generation lifter using legacy hardware.To say that senate designed the rocket isn't just false it a flat out lie that shouldn't be propagated at all. Yup. It was not done in a vacuum, contrary to internet myth and lore
Quote from: spectre9 on 11/30/2011 03:53 pmNASA and the senate went back and forth for a long time trying to figure out the best way to build a next generation lifter using legacy hardware.To say that senate designed the rocket isn't just false it a flat out lie that shouldn't be propagated at all. I do not claim that the Senate designed the rocket: I said that the Congress set the specs for it, which is a simple statement of fact--just read the Authorization Act. It has no business doing that: that's a job for engineers. Why has the Congress done this? Why hasn't reviewed the costs of various exploration options and directed NASA to pursue one of them?
I am suspicious about the whole affair. I would rather they built SLS than have no capabilities to send people Beyond LEO but with deep reservations.I am thinking what if Kennedy had demanded that NASA build a huge rocket with specific metrics and parts specified rather than setting a GOAL of getting to the Moon before the decade is out and leaving it up to NASA to figure out the best way to accomplish that mission.
That being said, I think what congress did was overly prescriptive and NASA should have been given enough autonomy to come up with whatever solution they thought was best without political pressure tipping the scales, I think that would be FAR better in the long run for the space program.
Quote from: spectre9 on 11/30/2011 02:01 amSLS isn't too big.It is if you bother to figure out how much it's going to cost to develop and fly. If NASA sticks with Block-1/1A then maybe. But trying to go for the BFR is a sure fire method to guarantee its cancellation because of the exorbitant cost.Look at it this way: it's going to cost just as much, if not more, than the Ares-I/V program and what caused that program to get cancelled? Wait for it - oh yes - cost. That's why I say that SLS is too big.Don't get me wrong - I love a BFR, I really do. But I love flying them even better. That means that we have to have something to fly. SLS Block 2 will cost way to much and will end up getting cancelled because of it. Then what?
Those studies are pretty much going through the motions. NASA always does "studies". Its a formality. They did those for constellation too, and the winning architecture was already determined by management. It all ends up looking like a way to dress up what was already been decided and make it look good.
Quote from: Starlab90 on 11/30/2011 12:34 amQuote from: Mark S on 11/29/2011 11:18 pmQuote from: Starlab90 on 11/29/2011 12:34 am3. What is "magical" about 105t is it is a requirement that has been imposed on the SLS Program by NASA HQ.What is the basis for this 105t requirement imposed by NASA HQ? It is not in the authorization act, so it should not be driving the SLS design in any way. It seems perfectly reasonable to postpone development of any advanced boosters until we actually need them.The information's not yet publicly available, but a number of the DRMs developed by the HEFT and HAT teams only require 105t. This includes both lunar and NEA DRMs.Unless there is a fuel depot involved, 105t seems to low for a Lunar landing mission. I have to believe this architecture includes the use of a fuel depot. Are you able to provide any details of what proposal are being considered?
Hopefully Shannon and his DRMs (followed up immediately with real objectives for making them reality) are made known to all soon.
"If the Congress were serious about exploring space, it would, after reviewing the likely costs, direct NASA to do so and leave NASA's engineers to choose the appropriate hardware. "Totally agree.
Is there any indications from the working group headed by John Shannon?(The one proposing missions for the SLS). Or have I missed it?
Quote from: oldAtlas_Eguy on 10/29/2011 06:10 pmSLS may not look like the best alternative to some (myself included) but from the perspective of the option that has funding, it is the best alternative until such time as something better with equal or more capability is public or privately funded.There were a lot of solutions trying to get the nod. All the champions of all those solutions all believed their solution was the correct one for NASA to pursue. In the end, it is the SLS configuration we currently have that has gotten the nod - and more importantly - the funding. No matter what we all think, it is this SLS that got the nod and it is this SLS that will take us back to the Moon.
Quote from: clongton on 10/29/2011 10:20 pmQuote from: alexw on 10/29/2011 08:29 pmQuote from: clongton on 10/29/2011 06:22 pm In the end, it is the SLS configuration we currently have that has gotten the nod - and more importantly - the funding. No matter what we all think, it is this SLS that got the nod and it is this SLS that will take us back to the Moon. It got funding this year. It remains to be seen whether it will get the funding necessary to sustain it next year, and the year after that, and so forth, for as long as required to get back to the moon. -AlexAh. Glass half empty kind of guy.No, he's just being a realist. CxP was the program of record and supported by Congress for years. How did that end up? You just have to hope for the best, and expect the worst. SLS being "the law" right now offers precious little guarantees for a few years down the line. Making progress and not wasting resources is NASA's best defense.
Quote from: clongton on 10/30/2011 01:42 amQuote from: Lars_J on 10/30/2011 01:51 amNo, he's just being a realist Pessimist. CxP was the program of record and supported by Congress for years. How did that end up? You just have to hope for the best, and expect be prepared to handle the worst. SLS being "the law" right now offers precious little guarantees for a few years down the line. Making progress and not wasting resources is NASA's best defense.Fixed that for ya Fixed a bit more; SLS is NOT CxP; for one it doesn't have the problem of a STICK to worry about; this is a one shot vehicle (rocket) with an evolutionary path that doesn't require two individual rockets following their own paths, to build a LV architecture; my apologies if my wording is wrong, but anyone who has been around here 2-3 years will understand; as well, we already have bent metal, in the form of the SSMEs, ET, and SRBs, with a Capsule (space craft), that is advancing in it's development path nicely, thank you very much; I'm not a glass half full kinda guy, I'm an optimist, that sees this as working out, IF, the pessimists can keep their hands off the PR; they are the only ones that are going to kill this, by the negative atmosphere they produce; Congress will play to which ever audience is the loudest; it is in their nature to please the squeaky wheel, so as to retain power;CheersGramps
In my opinion, SLS is too big and too expensive, unnecessarily so, but be that as it may, it will work well.
While I am not wildly enthusiastic about what NASA has done to the recommended configuration that the President signed off on in October 2010, the fact remains that it incorporates almost all the systems changes that we recommended. So it has that going for it. In my opinion, SLS is too big and too expensive, unnecessarily so, but be that as it may, it will work well. CxP was depending on a 2-vehicle solution that would have cost so much that no real missions would be affordable, and made some very bad design choices that drove it over the edge, thus imploding on itself. But there is something else going for SLS as well that wasn't a factor before that may derail any attempts to kill it. There is a burgeoning commercial industry which is on the verge of stepping up and taking NASA's place wrt human spaceflight. Regardless of all the accomplishments of the past, historic glory can only carry the space agency just so far and for the last 40 years NASA has not sent a manned spacecraft BLEO. Well we have several companies on the verge of equaling that, one of whom have already orbited their spacecraft and successfully recovered it "for reuse" no-less. And *that* spacecraft (Dragon) is being designed to enable BLEO missions to the moon in *direct* competition to NASA's unbuilt Orion spacecraft. I don't believe that the Congress is willing to let the national space agency be overwhelmed by private companies doing things that NASA can't do, and for less money than NASA's minimum budget, if only to save face and not let commercial companies humiliate it. If NASA is allowed to stumble at this point then it's game over for NASA. Congress knows that and in my opinion won't allow that to happen. SLS-Orion, for all its enormous bloat, will fly.IMHO, and YMMV.
.....But there is something else going for SLS as well that wasn't a factor before that may derail any attempts to kill it. There is a burgeoning commercial industry which is on the verge of stepping up and taking NASA's place wrt human spaceflight. Regardless of all the accomplishments of the past, historic glory can only carry the space agency just so far and for the last 40 years NASA has not sent a manned spacecraft BLEO. Well we have several companies on the verge of equaling that, one of whom have already orbited their spacecraft and successfully recovered it "for reuse" no-less. And *that* spacecraft (Dragon) is being designed to enable BLEO missions to the moon in *direct* competition to NASA's unbuilt Orion spacecraft. I don't believe that the Congress is willing to let the national space agency be overwhelmed by private companies doing things that NASA can't do, and for less money than NASA's minimum budget, if only to save face and not let commercial companies humiliate it. If NASA is allowed to stumble at this point then it's game over for NASA. Congress knows that and in my opinion won't allow that to happen. SLS-Orion, for all its enormous bloat, will fly.IMHO, and YMMV.
Quote from: clongton on 02/24/2012 05:11 pmIn my opinion, SLS is too big and too expensive, unnecessarily so, but be that as it may, it will work well. Would your "too big and expensive" opinion change much if the 3x J-2X second stage were dropped?
Quote from: clongton on 02/24/2012 05:11 pmWhile I am not wildly enthusiastic about what NASA has done to the recommended configuration that the President signed off on in October 2010, the fact remains that it incorporates almost all the systems changes that we recommended. So it has that going for it. In my opinion, SLS is too big and too expensive, unnecessarily so, but be that as it may, it will work well. CxP was depending on a 2-vehicle solution that would have cost so much that no real missions would be affordable, and made some very bad design choices that drove it over the edge, thus imploding on itself. But there is something else going for SLS as well that wasn't a factor before that may derail any attempts to kill it. There is a burgeoning commercial industry which is on the verge of stepping up and taking NASA's place wrt human spaceflight. Regardless of all the accomplishments of the past, historic glory can only carry the space agency just so far and for the last 40 years NASA has not sent a manned spacecraft BLEO. Well we have several companies on the verge of equaling that, one of whom have already orbited their spacecraft and successfully recovered it "for reuse" no-less. And *that* spacecraft (Dragon) is being designed to enable BLEO missions to the moon in *direct* competition to NASA's unbuilt Orion spacecraft. I don't believe that the Congress is willing to let the national space agency be overwhelmed by private companies doing things that NASA can't do, and for less money than NASA's minimum budget, if only to save face and not let commercial companies humiliate it. If NASA is allowed to stumble at this point then it's game over for NASA. Congress knows that and in my opinion won't allow that to happen. SLS-Orion, for all its enormous bloat, will fly.IMHO, and YMMV.Too big to fail... well, we've heard it before... I hope your right... because the alternative isn't pretty and will only delay things for years or more... Later! OL JR
Quote from: clongton on 02/24/2012 05:11 pm.....But there is something else going for SLS as well that wasn't a factor before that may derail any attempts to kill it. There is a burgeoning commercial industry which is on the verge of stepping up and taking NASA's place wrt human spaceflight. Regardless of all the accomplishments of the past, historic glory can only carry the space agency just so far and for the last 40 years NASA has not sent a manned spacecraft BLEO. Well we have several companies on the verge of equaling that, one of whom have already orbited their spacecraft and successfully recovered it "for reuse" no-less. And *that* spacecraft (Dragon) is being designed to enable BLEO missions to the moon in *direct* competition to NASA's unbuilt Orion spacecraft. I don't believe that the Congress is willing to let the national space agency be overwhelmed by private companies doing things that NASA can't do, and for less money than NASA's minimum budget, if only to save face and not let commercial companies humiliate it. If NASA is allowed to stumble at this point then it's game over for NASA. Congress knows that and in my opinion won't allow that to happen. SLS-Orion, for all its enormous bloat, will fly.IMHO, and YMMV.I respect your enormous knowledge on this subject but in my opinion you are overly optimistic at where SpaceX stands with Dragon, particularly with regards to BLEO flights.
Now that they have deleted the 5th SSME the next thing would be to go back to the STS ET capacity and fly the SRB with the central barrel omitted, a 4-seg SRB using the new designs. It will actually perform better than the as-designed SLS. Without the US it will lift in the neighborhood of 85 tons IMLEO. Add a single J-2X powered US and it will approach 120 tons.
Removing an SRB segment changes the thrust but not the burn time, right? Scaling all the masses and forces down by 20% would scale the payload down by 20% as well. In what way does your proposal differ from a uniform 20% reduction that enables it to perform better?
Quote from: Thunderbill on 02/27/2012 04:37 pmExcuse my ignorance but I take it from the article that the second test flight will be crewed and use the Delta IV Heavy Upperstage. When was this stage man rated?the first manned flight will be the 3rd flight of the Orion and the 2nd flight of the SLS. Orion will fly on a DIVH for its first flight in 2017 or so and SLS all flights following.
Excuse my ignorance but I take it from the article that the second test flight will be crewed and use the Delta IV Heavy Upperstage. When was this stage man rated?
Quote from: Thunderbill on 02/27/2012 04:37 pmExcuse my ignorance but I take it from the article that the second test flight will be crewed and use the Delta IV Heavy Upperstage. When was this stage man rated?Clearly, ICPS will be man-rated. If Delta IV Heavy CPS is the starting point for ICPS, there will have to be engine and flight control system modifications (to provide abort modes, etc.). Aerospace Corp. did a paper describing the needed mods a few years ago. It is all very possible. There is time - likely nine years from now until the first crewed flight.
Suppose that funding for the large upper stage never materializes. Is there a cheaper way to improve on block 1A to lift those rare payloads that want a bit more performance?
